1. Field of the Invention
The invention relates to a ventilation register for a vehicle such as heating and/or air conditioning registers, and more specifically, to a ventilation register for a vehicle which incorporates a Coanda effect passage to increase the efficiency of the register.
2. Description of the Related Art
A ventilation register for a vehicle typically comprises a fluid passageway interconnected at one end with a source of pressurized air at a preselected temperature and velocity, and at an opposite end with a grille which is directionally adjustable so that the air flow stream can be selectively directed into a passenger compartment of the vehicle. Examples of such prior art ventilation registers are shown in U.S. Pat. Nos. 5,129,858 and 4,957,036, issued Jul. 14, 1992 and Sep. 18, 1990.
A known scientific principle, generally known as the Coanda effect, relates to the placement of a body or other three-dimensional member within an air flow stream. The Coanda effect is realized by the tendency of the air to flow tangentially to the body and circulate around curves on the member, even through bends of 180.degree. or more. Some prior art ventilation registers have incorporated Coanda effect principles into the structure thereof. Examples of these prior art registers which incorporate Coanda effect structures therein include U.S. Pat. Nos. 5,259,815, 4,570,533, and 4,556,172, issued Nov. 9, 1993, Feb. 18, 1986, and Dec. 3, 1985. The tendency of the air to adhere to a curved surface through the Coanda effect typically aids the directional vanes placed at an exit point of the grille in efficiently directing air into the vehicle passenger compartment. These types of barriers typically have a large cross-sectional area which can also work to decrease the efficiency of the register.